All sellers making retail sales of taxable goods or services in Nebraska are required to register with the state and collect and remit sales tax. As Nebraska is a Streamlined Sales Tax state, out-of-state businesses without a sales tax obligation are encouraged to register for sales tax purposes.
Since the kinetic energy increases with the square of the speed, an object doubling its speed has four times as much kinetic energy. For example, a car traveling twice as fast as another requires four times as much distance to stop, assuming a constant braking force.
Knowing how your arrow speed changes with the increase in arrow weight, you can now easily figure out the new kinetic energy: For instance, if you know your crossbow shoots your current 400 grain arrows with a speed of 400 FPS, our chart above tells you to expect 124.8 ft-lb of kinetic energy at 30 yards.